Drilling in an area where metal shavings can cause catastrophic damage can be extremely tricky. I was recently faced with this task while modifying a vent for our upcoming Teryx project, and if I couldn't find a way to contain the metal particles while drilling, I would have been forced to remove the cylinder head. By keeping a drill bit coated with thick grease and cleaning it at regular intervals, I was able to drill the hole without the risk of loose particles going astray and entering the engine. A rag coated with the same grease was placed on the backside of the hole to catch any particles that would have unknowingly slipped through.